<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<script>
			console.log('1--------------')
			var str = "abc123";
			console.log(str.length)
			console.log(str.toUpperCase())
			console.log(str.charAt(2))
			console.log(str.indexOf('1'))
			console.log(str.lastIndexOf('c'))
			console.log(str.substring(2,4))
			console.log(str.substr(2,4))
			console.log(str.replace("a","*"))
			console.log(str.split(","))
			console.log(str.repeat(1))
			
			
			var d1 = new Date();
			
			console.log(d1)
			var d2 = new Date("2023/10/01 10:10:20");
			console.log(d2)
			console.log(d1.getFullYear())
			console.log(d1.getHours())
			console.log(d1.getMonth()+1)
			console.log(d1.getDate())
			console.log(d1.toLocaleDateString())
			console.log(d1.toLocaleTimeString())
			
			function hello(a,b){
				console.log(a)
				console.log(b)
				console.log(arguments)
			}
			hello(1,21);
			
			var ss = "6+7+8"
			console.log(eval(ss))
		</script>
	</head>
	<body>
	</body>
</html>